Welcome to Operating Systems: Three Easy Pieces (now version 0.90 -- see
book news for details), a free online operating systems
book! The book is centered around three conceptual pieces that are
fundamental to operating systems: virtualization,concurrency, and
persistence. In understanding the conceptual, you will also learn the
practical, including how an operating system does things like schedule the
CPU, manage memory, and store files persistently. Lots of fun stuff!

This book is and will always be free in PDF form, as seen below. For
those of you wishing to BUY a copy, please consider the following:

A wonderful
hardcover edition (v0.90) - this may be the best printed
form of the book (it really looks pretty good), but it is also the most
expensive way to obtain the black book of operating systems (a.k.a. the
comet book or the asteroid book according to students). Now just: $36.00

An almost-as-wonderful (and somewhat cheaper)
softcover edition (v0.90) - this way is pretty great too,
if you like to read printed material but want to save a few bucks. Now just:
$24.00

A pretty awesome
electronic edition (v0.90) - this is a nice
convenience and adds things like a hyperlinked table of contents, glossary of
terms, lists of hints, tips, systems advice, and a few other things not seen
in the free version, all in one massive DRM-free PDF. Just: $10.00

An alpha version for Kindle - Really, this is
just the PDF and does not (yet) include all the bells and whistles common in
e-pub books.

New: Can't bear to go out in public without an operating system? How
about an
Operating Systems: Three Easy Pieces T-shirt ? The t-shirt and
printed/electronic books are both brought to you by the demand
of various students and professors, and are a nice way to show your
appreciation.

INSTRUCTORS: If you are using these free chapters, please just link to
them directly (instead of making a copy locally); we make little improvements
frequently and thus would like to provide the latest to whomever is using it.
Also: we have made our own class-preparation notes available to those of you
teaching from this book; please drop us a line at remzi@cs.wisc.edu if you
are interested.

HOMEWORKS: Some of the chapters have homeworks at the end, which
require simulators and other code. More details on that, including how to find
said code, can be found here: HOMEWORK

BOOKS NEWS: A huge number of pictures added, chapters completed,
and other fun details in the latest stable version, 0.90. Track changes: NEWS

ACKNOWLEDGEMENTS: These students have greatly contributed to this
effort, through endless bug reports and other comments. Your name could go
here! (as well as in the printed book): ERRATA